1. Field of the Invention
The present invention relates to a method and to a device allowing to increase the pumping and the thrust performance for devices in which an induced fluid is used for driving another fluid by direct moment and energy transfers.
2. Description of the Prior Art
U.S. Pat. No. 4,485,518 by FOA describes a method and a device in which a direct energy transfer is efficiently performed between a primary fluid or working fluid and a fluid that is to be transferred over a certain distance. The improvement brought by FOA in relation to patent U.S. Pat. No. 3,046,732 by the same claimant consists in splitting the working fluid into two parts, in ejecting a first part through ports located on a rotor towards a fluid to be conveyed, and in using the fluid jet resulting from the second part of the working fluid passing through a central port for driving the first part of the working fluid and the fluid to be conveyed. This procedure minimizes shear in a fluid at the surface of a mechanical part and therefore possible fluid backflows which decrease the pumping efficiency of such a device. The bearings and the thrusts allowing rotation of the rotor are in contact with the fluid to be conveyed.
The prior art described in FIG. 1 comprises a rotary jet device in which a working fluid P under pressure is fed through a pipe 1' into a rotor 2' in which a major part of the working fluid flows our through ejectors 3' located on the rotor in the form of jets having an inclined direction so that the jets obtained cause rotor 2' to rotate. The rotor 2' is supported by a fixed external housing 7' by means for bearings 8' ensuring the rotation of rotor. Another part of the working fluid passes through a central pipe 10' prior to being mixed with an auxiliary fluid fed in through ports located in housing 7'. An interaction space 5' allows the mixing of the part derived through ejectors 3' and the passing of the mixture delivered by the central jet with the primary fluid K.
Such a device is not useful when the working fluid exhibits a high pressure and when the rotating speed of the rotor is high, because of the presence of bearings which wear out very quickly as a result of the motion of rotation and of the power of the jets.
The use of such bearings is inappropriate for applications where the fluids have high energies. In fact, the rotating speed of the rotor combined with the one-way ejection of fluids having high power values leads to a rapid wearing of the bearings and of the thrusts.
Moreover, the presence of particles, for example solid particles such as sand, decreases the reliability of such a device.